A CONTACT ELECTRORESISTANCE METHOD FOR IN-SITU INVESTIGATION ON METAL-SURFACE IN ELECTROLYTES AND SOME NEW POSSIBILITIES IN CORROSION AND ELECTROCHEMICAL STUDIES

A new method is developed for studying in situ the electroresistance o f films on metals and its dependence upon the electrolyte composition and potential. The method consists of measuring the contact electrores istance between two identical metallic specimens, periodically contact ed in electrolyte under potentiostatic control, in particular, between the walls of a fatigue crack in a sample cyclically loaded below the corrosion fatigue crack growth threshold. The sensitivity of the metho d is 10(-9) Ohm and it can be used for all conducting materials in any electrolyte at ambient and high temperatures and pressures in a wide region of potentials including the potentials of intensive evolution o f hydrogen or oxygen. The method allows the electroresistance of films on metals to be determined at very early stages of water and anion ad sorption, formation and destruction of hydride and oxide films, electr ochemical incorporation of cations, electrodeposition of metals and to study the kinetics of these processes. The water adsorption potential s meant to characterize quantitatively the hydrophility of metals have been specified for 16 metals.